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    <script>
        //2. 使用箭头函数实现对cookie的保存，读取，检测 三个函数重写

    // document.cookie = "username=Daisy Green";
    //document.cookie="username=John Smith; expires=Thu, 18 Dec 2043 12:00:00 GMT; path=/";

      let setCookie = (cname,cvalue,exdays)=>
        {
        var d = new Date();
        d.setTime(d.getTime()+(exdays*24*60*60*1000));
        var expires = "expires="+d.toGMTString();
        document.cookie = cname + "=" + cvalue + "; " + expires;
        console.log(6666)
        }
        setCookie("杨杨","50","6")


       
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        {
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            if (c.indexOf(name)==0){
           
                return c.substring(name.length,c.length);
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        }
        return "";
        }

   console.log(getCookie("cname")) 

    let checkCookie =()=>
    {
        var user=getCookie("cvalue");
        if (user!=""){
            alert("欢迎 " + user + " 再次访问");
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        else {
            user = prompt("请输入你的名字:","");
            if (user!="" && user!=null){
                setCookie("cvalue",user,30);
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    checkCookie()
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